User stories are a technique used in business analysis to represent a small, concise statement of functionality or quality needed to deliver value to a specific stakeholder. They are expressed by presenting the role, the goal, or the value and are a fundamental component of Agile methodologies. User stories help teams understand what the stakeholders need without going into excessive detail, allowing for iterative development and refinement of requirements.
References: The information is verified as per the Business Analysis Learning documents and resources, which discuss various techniques including user stories as a way to capture stakeholder needs and prioritize development of solutions12.